Extension circuit system



Filed Aug. 25, 1938 5 Sheets-Sheet 1 IIIlIIIIIIIIIIIIIII LOUIS M. POTTSATTORNEY.

Jan. 20, 1942. L. M. Pom

EXTENS ION G IRGUIT SYSTEM Filed Aug. 25, 1938 5 Sheets-Sheet 2INVENTOR. LOUIS M. POTTS A ORNEY.

Jan. 20, 1942. M. PoTTs 2,270,339

EXTENSION CIRCUIT SYSTEM Filed Aug. 25, 1938 5 Sheets-Sheet 5 24| FIG. 8

v I; F |G.'9

INVENTOR.

LOUIS M. POTTS Y ATTORNEY.

Jan. 20, 1942. o s 2,270,339

EXTENS ION CIRCUIT SYSTEM FiledAug. 25, 1958 5 She ts-Sheet 4 ATTORNEY.

v Jan. 20, 1942.

L. M. POTTS EXTENS ION CIRCUIT SYSTEM Filed Aug. 25, 1938 FIG. H

a 239 220 209 my 331 341 4 302 "224 I) D D D) D) I) I) r) 325 327 i I I324 m 304 ggg 4 IiiDJDIDDTIDDIII f ('6) 5 Sheets-Sheet 5 INVENTOR. LOUISM. POTTS ATTORNEY.

Patented Jan. 2( 1942 2,210,339 axrsusron cmcurr SYSTEM Louis M; Potts,Evanston, 11L, assignor to Teletype Corporation, Chicago, 111., acorporation of Delaware Application August 25, 19:8, Serial No. 226,729

sa'oial m. cl ire-52) .and it is a still further object of'thisinvention Thisinvention pertains to synchronous multiplex telegraphsystems in which a channel of the system is equipp d at its ends withsignal receiving and translating devices connecting the channeloperatively over further or extension line channels to remotesubstations. Specifically, the invention pertains to such systems inwhich the extension line channels may be single wire channels operatedupon the two-way simplex system of start-stop telegraphy.

The object of the invention is to provide a simple and inexpensivemechanical means for translation of signals and for retransmission oftranslated signals from a first simplex line into a multiplex systemarid'from the multiplex system into a second simplexline.

To effect the above result, mechanical devices are required in twoclasses, first an extensor having the functions of receiving start-stoppermutation code signals from a substation at irregular intervals or atthe maximum speed of which the substation is capable of storing thesgnals and of supplying the stored signals to a multiplex distributorcommutator in such manner that the multiplex distributor may retransmitthe stored code signals into a multiplex channel, and second, anextensor having the functions of receiving permutation code signals fromsaid multiplex channel and retransmitting them in the form of start-stopcode signals into an extension line channel. G

Since each extension circuit of two-way simplex transmission nature mustbe connected to the first extensor for receiving code signals from thesubstation and to the second extensor for transmitting code signals tothe substation, it is a further object of this invention to provide echosuppression signals preventing signals generated by the second extensorfrom regenerating any signal in the associated extensor.

It is a feature of this invention to provide a system of apparatus fortransmitting a break signal through a multiplex channel by creating uponone simplex line a break signal of extended length and of spacingnature, translating the said break signal into a repeated permutationcode signal, transmitting the repeated permutato embody the said breaksignal translating means mechanically in the structure of the re- Ispective extensors and to provide therein contacts for controllingsignal lamps which will indicate a break signal or an accidental breakin a line circuit,cidentifylng at the same time th extension clrcuit inwhich the break has occurred. The recited objects and features ofinvention are attained by adding to a multiplex system, according to thepresent practice, only the required number of first and second 'extensorma-' chines, with no modification of substation equip-' ment upon thesimplex lines and with a minimum modification of the distributingcommutators within the multiplex system.

As illustrated in detail herein, a system of apparatus according to thisinvention comprises a multiplex line of a plurality of channels havingcustomary terminal apparatus of transmitting multiplex distributor andreceiving multiplex distributor with whichis combined, for each or forany channel, a pair of mechanical translating devices. One of thetranslating devices has functions of receiving start-stop permutationcode signals from a simplex line, storing the group of permutationelements of each code signal, and delivering the stored group ofpermutation elements to the transmitting multiplex distributor in propertiming to effect transmission of the permutation group over a multiplexchannel. The other of the pair of translating devices has functions ofreceiving th transmitted group of permutation elements from themultiplex channel and immediately retransmit ting the permutation groupwith added start and stop signals to form a complete start-stoppermutation code signal'upon a further simplex line.

' remains stored until the transmitting multiplex distributor reaches asignaling position, when a local signal from the transmittingdistributor causes transfer of the stored combination to be tion codesignal through the multiplex channel,

impressed upon commutator segments for immediate transmission over themultiplex channel.

. Three cam sleeves are provided on one motor driven shaft in thistranslating device, the first cam sleeve being responsive to a startingsignal received from the start-stop simplex line and the second camsleeve being started at conclusion of the received code signal toqualify for operation -bination of impulses in the simplex line.

the retransmitting cam sleeve which is started in response to a startingsignal from the transmitting distributor and which immediately transfersthe stored code signal to segments of the multiplex distributor fortransmission.

In the second mentioned translating device, a set of magnets and latchesoperate in response to received im ulses to register a received codesignal after which a local impulse from th receiving distributor to thetranslating device causes the registration to be transferred to a camtype start-stop distributor which immediately transmits a fullstart-stop code signal embodying the stored code signal to an extensionsimplex line.

Apparatus for transmitting the break signal as above described isembodied in part in the first mentioned translating device in the formof a means responsive to presence or absence of the stop impulse whichnormally follows a code com- Upon opening a substation break key in thesimplex line, the signal transmitted and received by the first mentionedtranslating device is equivalent to blank code signal repeated withoutany stop impulse. Absence of stop impulses causes the translating deviceto retransmit figures shift code signal repeatedly into the multiplexchanhel.

Further apparatus for transmitting the break signal is added to thesecond mentioned translating device in the form of a ratchet and drivingpawl. figures shift code signal to drive the ratchet. step by step andafter three or more steps, the

ratchet operates a switch to open the extension simplex line, thusreproducing in the receiving extension circuit the breaking conditionset up by the break key in the originating extension circuit.

A better understanding of the invention may be attained from thefollowing description, taken in conjunction with the accompanying drawings, wherein i Fig. 1 illustrates a general circuit arrangementembodying the invention;

Fig. 2 illustrates, in a theoretical mechanical diagram, details ofstructure of an A extensor taken as of a vertical section through anaxial plane of the power shaft of the extensor;

Fig. 3 illustrates the structure of an A extensor in theoreticalmechanical diagram taken as at right angles to the diagram of Fig. 2;

Fig. 4 shows a further detail of the structure of Figs. 2 and 3;

Fig. 5 shows detail of starting mechanism for starting the A extensormechanism under control of a received starting signal impulse;

Fig. 6 shows another view of the mechanism of Fig. 5;

Fig. 7 shows, in theoretical mechanical diagram, details of. structureof a B extensor machine taken as an elevational view sectioned acrossthe axis of the power shaft;

Fig. 8 shows further detail of the structure of Fig. 7 taken as anelevation at right angles to the view of Fig. 7;

Fig. 9 shows a detail of the view of'Fig. '7;

The pawl responds to a received Fig. 10 ShOWs details of the mechanicalstruc- Fig. 13 shows a detail oi the structure of Fig. 10; and 1 Fig. 14shows a detail of the structure of Fig. 7.

Referring to Fig. 1, rectangles II and i2 represent A extensors,rectangles l3 and ll represent B extensors, rectangles l5 and I6represent substations, the substation i5 being connected to A extensor ii by line conductor l'l, the A extensor ii being connected by cable 18and local signal conductor l9 to a transmitting multiplex distributor itwhich is connected over a line conductor ii to a receiving multiplexdistributor 22, which is connected by cable 23 and local signalconductor 26 to B extensor machine M, which is connected further byconductor 25 through windings 26 of magnets 21 and thence over lineconductor 28 through substation it to ground connection. The elementshere recited from IE, IT to 28, and it have been mentioned in the orderof transmission of communication from substation it to substation it. Afurther conductor 29 connects B extensor it to'A extensor I2 and currentover this conductor prevents the armature of magnet 21 in extensor i2fromresponding to signals transmitted through winding 28 of that magnet.Identical apparatus and circuits are shown for transmission ofcommunication signals irom substation is to substation it through Aextensor 52, line conductor 3|, B extensor i3, and through a magnetwinding 32 of magnet in A extension it with similar provision ofconductor 30 for echo suppression.

Structure of an A extensor machine tail in Figs. 2 to 6, inclusive, andin exploded perspective in Fig. 10. It comprises a power shaft 35 whichrotates continuously by power received through gear 36 and which bearsfixed thereupon the continuously moving parts of three clutches whichdrive intermittently three start-stop cam sleeve members; namely, apermutation code signal receiving cam sleeve, or code cam sleeve 37, ablocking cam sleeve 38, and a retransmission function cam sleeve 40.

Code cam sleeve 31 is driven by friction clutch il, d2 under tension ofspring 83 and is restrained in its stop position by stop arm 44 undercontrol of code signal magnet 45, as illustrated in Figs. 5 and 6. Camsleeve 31 bears five combinational cams t6 and an operating cam 41.Blocking cam sleeve 38 is driven by a friction clutch 50 whose powertake-oil member 5i has a spline projection 52 passing through a radialslot at the apex of a cam 53 on cam sleeve 38. The cam sleeve 38 and thetake-off member 5| are restrained in stop position by a latch 54 whichengages the spline projection 52 and is arranged to release the frictionclutch El under control of cam 31 through operation 01 a train ofmembers including 90, 92, 93, 94, and 95, as described in detail below.Cam sleeve 38 bears blocking cam 55, sixth impulse cam 56, and firsttransfer cam 57, in addition to the mentioned cam 53.

Retransmission function cam sleeve 40 is driven by a toothed clutch 59whose power member 60 is pinned to shaft 35 and whose sliding takeoffmember BI is splined to cam sleeve 40, is urged by spring 62, and isrestrained from engagement with power member 60 by detent 63 under jointcontrol of magnet 64 and of cam 55 on cam sleeve 38.

Sliding clutch member 6! bears crown cam 68,

while cam sleeve 48 bears second transfer cam 65, deleting cam 66, andresetting cam 81.

I In Fig. 2, operating springs and retractile springs, other than clutchsprings. are omitted to simplify the drawing. The three clutches and camsleeves are related as follows: Reception is initiated by release of thearmature of the code signal magnet which starts the code cam sleeve, andjust before the endoi' its rotation the code cam sleeve starts 1rotation of the blocking cam sleeve which, in its initial angle ofrotation, withdraws a blocking latch and unlocks the armature of magnet64 to respond to electromagnetic control.- Retransmission is initiatedby receipt of a controlling impulse in magnet 84 from a multiplexdistributor, to start rotation of the retransmission cam sleeve.

With code signal magnet 45 energized, its armature 12, Figs. 3, 5, and18, and armature carrier '82 are held attracted in counterclockwiseposition upon pivot 48. Its striker 13, shown as an adjustable screw, isheld in its marking position.

A rocking lever 14 engages and latches a rotary gate member 15, Figs. 5and 10, which engages g5 and restrains the stop arm 44 of code camsleeve 31. Upon de-energization of magnet 45 in response to a receivedstarting impulse of spacing nature, retractile spring 16 rotatesarmature carrier 82 upon its pivot 48, causing striker 13 to 88 operatethe sliding pin 11, which rocks a bell crank lever 18 clockwise upon itspivot 18, thereby rocking the lever 14 upon its pivot 88 against tensionof compression spring 8i, Fig. 6, to unlatch the rotary gate member 15.Armature lever 82 is restored to its operated position shown by a camlobe 88, Fig. 10, on cam sleeve 31 in engagement with a cam follower I88on armature lever 82.

In rotation of cam sleeve 31, five code cams 46 do operate successivelyfive code cam followers 83,

Figs. 3 and 10, about a common pivot 84 against tension of individualsprings 85, thus drawing five code swords 86 momentarily against amarking anvil I36 or spacing anvil I31 carried by an armature subleverI38, accordingly as armature lever 82 may be at the instant in itscounterclockwise position in response to a received marking signalimpulse or in its clockwise position in response to a received spacingsignal impulse. 68 Armature sublever I38 is operated by adjustablestriker I48 on armature lever 82 against which it is drawn yieldably byspring I46. By engagement with marking or spacing anvil of armaturesublever I38 to form a fulcrum, and by power received from code camfollower 83 through a socket articulation, the five code swords 88 arepositioned in clockwise or counterclockwise position severally, andthereafter are pressed against one arm of five code T-levers 81 byindividual springs 85, go rotating the'T-levers and shifting the fivecode slides 88. A sixth equipment comprising code sword, T-lever andcode slide is described under Break signal structure later herein. Amore complete description of the code signal respong5 sive'apparatus ofFig. 3 may be had from Patent No. 1,904,164 issued to S. Morton et a1.

Bell crank cam follower 88 pivoted at 8i, Figs. 2, 3, and 10, ispositioned in the path of cam 41, Figs. 2 and 3, and operatesmomentarily just be- 78 fore cam sleeve 31 stops, to rock an arm 82fixed to a rocking shaft 83, Figs. 2 and 10, to which is fixed an arm84, which engages and rotates clockwise, a spring-urged trigger 85pivoted at 86 I which, when rotated clockwise by arm 84, re- 75 leasesthe clutch latch member 54. Retractilo. spring 81 rotates the member 54on its pivot 58. drawing the member 54 out of the path of spline 52. Acam follower roller 88 is mounted upon member 54 and is positioned inthe path of cam 53, Fig. 2. Engagement of cam- 53 and its follower 88rotates member 54 on its pivot to relatch the member 54 and trigger 85.

While the blocking cam sleeve 38 is in its position of rest, the apex ofcam 55, Figs. 2, 4, and 10, holds cam follower MI in blocking positionupon its pivot I82, and a connecting spring I88 also holds the rockingmember I84 in blocking position upon the common pivot I82 and in'abutting engagement through mechanical contact I18 with follower I8I,thus maintaining a blocking latch member 58 upon member I84 in positionto engage an armature lever 18 carrying armature II of magnet 64 toprevent more than a negligible movement of armature H. In any otherangular position, apex 55 permits follower I8I and its associatedmembers I84, 68 to rotate under tension of spring I86, which willposition blocking latch 68 to clear the path of extension arm 18.

Sixth impulse cam 56 is positioned to operate its follower II8, Figs. 2and 3, at an early instant in rotation of cam sleeve 38. Cam follower H8is fixed to a rocking shaft III which carries also an operating arm II2articulated by socket connection to sixth sword H3.

The apex of first transfer cam 51, Figs. 3 and 18. is positioned torestrain its follower II4 while cam sleeve 38 is at rest and to operateits follower H4 and jockey blade 88 into transfer locking position soonafter operation of cam follower II8 when cam sleeve 38 has started.Follower II4 is pivoted at II5, Figs. 2 and 10, and has an operating armII6, Figs. 2, 3, and 10, which carries a jockey blade 88 engaginglocking projections of six storage slides 88. Operation of follower II4by arrival of cam 51 at stopped position lifts the blade 88 from slides88.

Armature lever 18 normally is held in its position shown in Figs. 4 and10 by attraction of differential magnet 64 and is blocked againsteffective retractile operation by blocking latch 68. Armature lever 18is fixed upon rocking shaft II'I upon which shaft the clutch detent 63is rotatably carried. Detent 63 has an adjustable striker screw I I8 inengagement with armature lever 18, the two members 63 and 18 being heldin engagement by a spring II8. When armature H is in attracted positionas shown, the distal end of detent 63 is in position to be engaged bycrown cam 86 on sliding clutch member 6|. When armature II has beenreleased by de-energization of magnet 68, retractlle spring I28 rotatesthe armature lever 1I and detent 63 to remove the end of detent 63 fromcrown cam 68, thereby releasing the sliding member 6| under tension ofspring 62 to engage power member 68 to drive the cam sleeve 48.

The apex of cam 65 on cam sleeve 48 is positioned to operate itsfollower I2I soon after starting of rotation of transmission sleeve 48.Follower I2I is of yoke shape pivoted at I22 with an integral arm I23which is connected through a link I24 to a pivoted arm I25 under tensionof spring I26, Fig. 3, and rocking upon a fixed pivot I21. The distalend of arm I25 bears a stud I28 which constitutes a common pivot for sixtransfer members I38, each of which is connected through a ball and slotarticulation to one of six individual bell crank levers I3I havingoperating arms I32 which control the position of electrical contactsprings l33. All levers I 3| are pivoted upon a common fixed stud I34,and each is held in either of its two positions by an individual jockeyI35.

The deleting cam 66 operates its follower I40 momentarily upon its pivotI4I near the end of rotation of cam sleeve 40. Pivoted upon the fixedpivot stud I34 is a yoke lever I42 bearing an integral bail blade I43shaped to engage all of the six bell crank levers I3I. Members I40 andI42 are articulated by an extension finger I44 on member I40 ridingagainst an extension I41 of member I42.

The apex of resetting cam 61 on cam sleeve 40 operates its follower I45at any median point in its rotation and the apex passes the followerbefore stopping, thus leaving the follower free to fall at any instantduring the period of-rest of the cam by reason of de-energization ofmagnet 64 and release by latch 66. Follower I45 is pinned to rockingshaft II1 to which armature lever 18 also is pinned, each operation offollower I45 thus returning lever 10 toward magnet 64, thereby drawingclutch detent 63 through spring I16 into position to be engaged by crowncam 58. By this movement of armature lever 18, the blocking end thereofis withdrawn from the path of blocking latch 66, permitting the latch 69to move into blocking position.

Crown cam 68 on sliding member 6! of clutch 59 engages the end of detent63 and the member 6| slides in response to that engagement, thusdisengaging itself from power member 60, interrupting transfer of powerfrom member 68 to member 6i.

Referring to A extensor II, Fig. 1, magnet 55 is held energized duringperiods of nontransmission by current through its windings 32, which arecomponents of the extension line circuit including battery I51, resistorI52, retransmission contacts I53 of B extensor I3, closed contact I55,central station local conductor I55, windings 32 of code signal magnet85 in A extensor II, extension circuit line conductor I1 to substationI5, break key I56, transmitter contacts I51, slowto-release break signalrelay I58, recorder selector magnet I58, and ground. Differential magnet64 is held energized during periods of nontransmission by currentthrough its winding I60 which is included in a local circuit withbattery I6I, resistor I62, and ground. An operating circuit fordifierential magnet 64 includes battery I6I, resistor I62, winding I63of magnet 64, local central station conductorlil, segment I64, andbrushes I65 of multiplex distributor 20 and ground.

Retransmitter I10 in A extensor II, Fig. l, includes six electricalcontact springs I33, Figs. 1, 3, and 10, adjustable into markingposition by six transfer members I30, Figs. 2, 3, and 10, and intospacing position by bail blade I43. Five contact springs I33 numbered 1to 5 and shown in spacing position in Figs. 1, 3, and 10, arecontrollable through five cam followers 83, and one contact spring I33No. 6, shown in marking position, Fig. l, is controllable through cam56, Fig. 2. Contact springs I33, Nos. 1 to 5, are connected throughcable I8 to segments 1 to 5 of multiplex distributor 20. Markingtransmission battery I12 is connected through resistor I13 to markingcontacts I14, Nos. 1 to 5, and to spacing contact I15 of springs I 33,No. 6, in the transmitter I10. Spacing transmission battery I16 isconnected through resistor I11 to spacing contact of spring I33, No. 3,and to marking contact of spring I33, No. 6, and when contact springI33, No. 6, is in marking position, as shown, the spacing batteryconnection is extended through a local conductor I18 to spacing contactsof springs I33, Nos. 1, 2, 4, and 5.

The maximum speed of operation of the transmitter at substation I5 isless than the speed of operation of distributor 28 at the centralstation.

Operation of the A extensor machine Operation of the A extensor machineII, Fig. 1, illustrated in detail in Figs. 2 to 6 inclusive and Fig. 10,is as follows: Upon receipt over line conductor I1, Fig. l. of astarting spacing impulse of an incoming start-stop code signal, codesignal magnet 45, Fig. 3, releases armature 12 which moves armaturecarrier 82 and striker 13, Figs. 3 and 5, to operate pin 11, Figs. 5 and6, bell crank lever 18, and rocking lever 18 to unlatch gate 15 whichreleases stop arm 86 and permits a revolution of selector cam sleeve 51.The five cams Z6 cooperate with the armature 12, armature lever 82 andarmature sub ever I36 of code signal magnet 45 to adjust the five swords86 in code manner in response to the received permutation code signal.Cam 81 then operates the bell crank cam follower 36, and the cam sleeve31 stops with the armature lever 82 in marking position.

Cam follower 95, rocked. momentarily by cam 81, operates throughelements 92, 83, 94 and 85 to unlatch the member 55 which is operated byits spring 91, Fig. 3, to release spline 52 of clutch 5i, thus startingthe cam sleeve 38. The first operation by cam sleeve 38 is effectedthrough its cam 55, Figs. 4 and 10, which moves its apex away from itsfollower I81 pivoted at I02, and through spring I63 and mechanicalcontact extension I19 permits spring I86 to rock the member I04 uponpivot I82, thereby rocking the blocking member 69 away from the end ofarmature lever 18 and clearing a path for operation of lever 10, so thatarmature 1! may be operated by spring I20 when released by magnet 64.This condition maintains until cam sleeve 38 completes its rotation. Thesecond operation by cam sleeve 38 is effected through its cam 56, Figs.2 and 3, which operates momentarily its cam follower H0, Fig. 3, uponrocking rod III which has fixed upon it an arm II2 with socketarticulation to a No. 6 sword H3, which by reason of the markingposition of the armature 12 of selector magnet 45 at this time by "stopsignal! or resting time current, results in setting sword II 3 intomarking position, as shown in Fig. 3. The third operation by the camsleeve 38 is efiected through its cam 51 which releases its cam followerH4 and rocks the member H4 upon its pivot rod H5, Fig. 2. Member II4carries upon its arm II 6 a jockey blade 89.which now holds in adjustedposition the six signal storage slides 88. Locking the slides 88 permitsoverlap, a second code signal being stored in swords 86, after whichlifting of the blade 89 will permit the slides 88 to respond to springs85 acting through swords 86 and H3 and T- levers 81 to position the liveslides 88 in accordance with the marking or spacing nature of the fiveimpulses of the stored code signal and to position the sixth slide 88into marking position in accordance with the marking condition of magnet45 and its armature 12 at the instant of reoperation of cam 53 and camfollower I I 0. The

received signal 'and the marking nature of the tain the arm I 3I inrocked position.

two windings of which I60 has a continuouspolarizing current sufiicientto hold its armature attracted and sufllcient to re-attract its armatureafter a small" angular movement permitted by engagement of members 69and I0, Fig. 4, after release of armature II when member 69 is inblocking position.

Release of armature 'II' by magnet 64 is effected by a current in thesecond winding I 63 of magnet 64 under control of the multiplexdistributor over conductor I9, segment I64 and brush I65, the currentreceived from the multiplex distributor being in reversed magneticeifect compared with the magnetic effect of the described polarizingcurrent, so that the magnetism of magnet 64. is reduced or cancelled byreceipt of the signal from the multiplex distributor, and armature II isreleased by reason of reduced or neutralized magnetism. Should the camsleeve 38 be in stop position; holding the follower IN and latch 69 inobstructing position, armature lever I0 will move slightly to engage thelatch 69 and shortly thereafter will be re-attracted by magnet 64, whenthe signal from the multiplex distributor is terminated. This reversemethod of operating an armature is suited to the conditions hereindescribed because a quicker response of armature II is attained comparedwith its response to direct energization of magnet 64. Release ofarmature II permits its attached arm I0, Fig. 4, to move the detent 63of sliding clutch member 6| so that cam sleeve 40 is started and isdriven with ample power by its toothed connection to the motor shaft 35.The first operation by cam sleeve 40 is effected through cam 65, whichengages and moves momentarily its follower I 2| pivoted on rod I22 andhaving an arm I23 bearing a stud which operates a link I24 to carrypivot rod I28 and its six transfer members I30 into engagement with thesix slides 88, thereby rocking the members I30 upon the rod I28 in codecombinational manner and rocking the bell crank arms I3I, Figs. 3 and10, upon their common pivot rod I34, each such arm having a detentengaging an individual jockey I35 to re- A bell crank arm I32, upon eacharm I3I, controls an electrical contact member I33, and thus sets up anelectrical storage corresponding to the mechanical storage in slides 88,so that the five combinational impulses are registered upon fiveelectrical contact members I33 and are connected to multiplexdistributor segments for transmission over a multiplex channel The sixthcondition is set up upon a sixth contact member I33,,No. 6, Fig.1, inresponse to the position of the No. 6 sword II3, Fig. 3.

The brushes of the multiplex distributor now transmit to the multiplexchannel the signals set upon the five contact members I33, Nos. 1 to 5.During such transmission the cam 53 engages its follower roller 88 andrestores the latch member 54. Cam sleeve 38 then reaches its stopposition in whiclrposition cam 55 operates follower IOI extending thespring I03 and pressing the finger 69 against the end of armature leverI0.

Sleeve 40 then performs its second operation effective through cam 86,which engages and rocks its cam follower I40 momentarily. Member I 40 ispivoted at I and bears a finger I44 projecting into engagement with ayoke lever I42 pivoted upon pivot rod I34, which is the common pivot rodof all arms I3I'. The momentary motion of member I40 is imparted tomember I 42 which carries a blade I43 common to arms Nos. 1 to 5 of thesix signal arms I3I, The blade I43 engages any arms I3I, Nos. 1 to 5,which have been elevated by transfer members I30 and depresses allengaged arms into spacing position as shown in the drawings where alldepressed arms are retained by the individual jockey springs I35,

so that the electrical storage of the code signal transiently efiectiveupon contact members I33, Nos. 1 to 5, is deleted. Arm I3I', No. 6, isnot so restored. since the normal position of that arm is markingposition.

Cam sleeve 40, as a final controlling act efiecx tive through cam 81 andits cam follower I45, rocks the shaft Ill and restores-armature II andits armature lever I0 into resting position, as shown in Fig. 4,permitting detent 68 to assume its locking position in the path of leverI0 and bringing the armature II near the polesof magnets 64 so that thepolarizing magnetic energization of magnet 64 seizes and holds thearmature II, thus holding clutch detent 63 in position to be engaged bycrown cam 68.

The last act of the cycle of the A extensor oc-- curs when the crown cam68 upon clutch member 6| engages detent 63, resulting in sliding themember 6| out of engagement with clutch member 60, thus stopping therotation of member 6| and of cam sleeve 40. Jockey lever I82, urged by,spring IBI, presses its roller cam follower I83 into a notch in cam I84on sleeve 40, operating to force sleeve 40 into its stop position and toprevent clutch 59 from grinding.

Structure of B errtensor machine and cam follower-206 pivoted at 201. Tothe cam follower 206 is fixed the armature 208 of magnet 2I0.

Cam sleeve 204, Figs. 7 and 14, bears six cams 2| I, five of which arecode combinational cams having individual bell crank followers 2I2 eachcontrolling a combinational code contact pair 2| 3 and each having alatch end 2 engageable by an individual one of five bell crank latches2I5 mounted on a common pivot stud 2I6. A sixth bell crank follower 209,Fig. 14, mounted upon pivot stud 2II common to the five followers 2I2,is similar to followers 2I2 except that it has no latch end 2I4 norlatch 2I5, and it controls a stop impulse contact pair 2 I8.

Cam sleeve 204 bears also a cam 2I9 having a followerk220 pivoted onstud 2i! and controlling a contact pair 22I. Also on cam sleeve 204 aretwin cams 222 of three radial dimensions and a cam 228 controlling afollower 224 pivoted on common stud 2H and bearing a bail blade 225which spans the five bell crank followers 2I2 of the five codecombinational cams 2H and of the five latches 2| 5.

Upon the frame of the machine 226, Fig. 11, are mounted five codecombinational signal impulse receiving magnets 230 each havingindividual armatures 23I, sliding rods 232, pivoted latches 233, andsignal impulse storage members 234. The five storage members 234 arepivotally mounted upon a common stud 235 and have individual operatingarms 236 shaped to engage individually arms of the five bell cranklatches 2I5.

The mentioned twin cams 222 have twin followers 239 formed as extensionends of a cam follower yoke 240 having both arms pivoted upon stud 2I1.Yoke 240 carries a bail. blade 24I spanning the five operating arms 236.Spring 242, Fig. '1, urges the follower yoke 240 to hold its bail blade24I against arms 236, but is weaker than any one of the five springs243, so that any one of the springs 243 may rotate its associated member234 to overcome the spring 242 and rotate the followers 239 intoengagement with cams 222, in response to a receivedmarking signalimpulse.

Operating yoke 240, through an extension member 241, Fig. 12, engageslever 244 pivoted at 245 and controls the lever 244 through a spring 246and an adjustable striker screw 248. An arm 2490f the lever 244 has itsend positioned to block movement of cam follower 206, thus preventingmagnet 2I0 from operating the member 206 and clutch 202, Fig. 8, unlessat least one impulse storage member 234 is set to marking position,thereby setting bail blade 24I into its median position as will bedescribed, and moving arm 249 of lever 244 out of the path of 9. lug 254on cam follower 206.

Referring to Fig.1, the B extensor I4 has its five magnets 230 connectedin series with battery 250 and resistor 25I and through cable 23 tosegments 1 to 5 of multiplex distributor 22. Segment 252, No. 6, of thedistributor 22 is connected through local conductor 24 to magnet 2! inseries with battery 253. A retransmission circuit extends from battery255, resistor 256, code contact pairs 2 I 3, and start-stop contact pair2 I 8, closed contactor pair 251, local conductor 25, windings 26 ofmagnet 21 in A extensor I2, extension line conductor 28 to substation I6and through break key 258, contacts of transmitter 259, slow-to-releaserelay 260, and selector magnet 26I to ground return. A further circuitfor echo suppression includes battery 262, resistor 263, windings 264 ofmagnet 21, local conductor 29, contact pair 22I, and ground return.

Operation of B extensor machine Brushes 265 in distributor 22 pass oversegments 1 to 5, and magnets 230 are energized in combinational mannermoving the associated triggers 233 and storing the marking signals instorage members 234. Storage members which have been operated inresponse to marking signal impulses move latches 2I5 to a mean positionwithout effect and move bail blade 24I and yoke 240 to the effect thatyoke 240 operates lever 244 and removes its blocking arm 249 from thepath of extension 254 on cam follower 206.

Brushes 266 then engage segment 252, No. 6, and cause energization ofmagnet 2I0, which operates armature 208 and cam follower 206, to operatethe clutch 202 and to start the cam sleeve 204.

Cam 2I9 permits its follower 220 to close its contact pair 22I, thusenergizing magnets 21 through winding 264 and rendering the magnets 21unresponsive to signals in line conductor 28. Cams 222 then present aminimum radius and permit followers 239 and bail blade 24I to releaseall operated storage arms 236 which individually operate correspondinglatches H5 and release corresponding bell crank followers 2I2, whereuponcams 222, by highest radius, operate yoke 240 and bail blade 24! torestore all operated storage members 234 into latched relation with thetriggers 233. Yoke 240 also restores lever 244 and arm 249 and relockscam follower 206.

At this time cam follower 209 .and contacts 2I8 have transmitted astarting impulse. Cam followers M2 and contacts 2I3 now transmit codesignal impulses over the line circuit including battery 255, resistor256, code contact pairs 293, local conductor 25, winding 26 of magnets21, extension line conductor 28, and substation I6 to ground.

After transmission of the code signal impulses, cam follower 209 closescontact pair 2I8 for the stop signal impulse and cam 2I9 operates itsfollower 220 to reopen contact pair 22I.

' Should brushes 265 not operate any magnet 230 by a received markingsignal impulse, the ensuing impulse from segment 252 will energizemagnet 2I0, but armature 208 will remain blocked by I member 249, clutch202 will not be operated, and

a blank" code combination received over the multiplex channel 2| will besuppressed and will not be retransmitted over the extension lineconductor 28.

Break signal structure The break signal structure comprises in partseveral elements encountered above; namely, break key I56 andslow-to-release relay I58 at substation I5, similar equipment 258, 260at substation I6, Fig. 1, cam 56 andfollower arm IIO, rocking shaft III,Figs. 2 and 3, operating arm II2, sword Il3, T-lever 81, No. 6, storageslide 68 No. 6, transfer element I30 No. 6, bell crank lever I3I No. 6,contact member I33 No. 6, Figs. 1 and 3, local conductor I18, Fig. l,and contact pairs I54 and 251, Fig. 1.

Additional structural elements pertaining to the break signal system areillustrated in Figs. 7, 9, 11 and 12; namely, a cam 300 on cam sleeve204, Figs. 7 and 11, having a follower 30I pivoted on common pivot stud2" under tension of spring 302 and carrying upon a movable pivot 303 adriving pawl 304 and a rocking member 305 urged by a spring 306 againsta stop lug 3 I0 and having a detector bail blade 301, which ispositioned to engage undercut lugs 308 formed on bell crank latches 2I5Nos. 1, 2, 4, and 5, when in latching position, as shown, and to engagelug 309, Fig. 9, on bell crank latch 2I5 No. 3, when that latch is innonlatching position by control of its associated impulse storing member234, 236, after receipt of a No. 3 signal impulse of marking nature.Bail blade 301, when operated, will engage at least one of the five lugs308 and 309, except that when latches 2I5 are set for the codecombination, marking, marking, spacing, marking, marking, or figuresshift code signal, the bail blade 301 will pass under all lugs 308 andover the lug 309 without engaging any of the said lugs. Any other codesignal may be chosen in place of the figures shift codesignal heredescribed for illustration.

Upon a stud 3, Figs. 7 and 12, is rotatably mounted a cam member 3I2having a cam apex 3I3, a stop pin 3, a series of ratchet teeth 3I5, andr. retractile spring 3I6 urging the cam member and its stop pin 3l4against a shoulder of a stop arm 3I8 pivoted upon the stud 3II and Iadjustable by a clamping member 3I9, which passes through a slot 320 ina frame member 3". Ratchet teeth3l5 are engaged for propulsion bydriving pawl 304 and are engagedfor retention by detent pawl 322 pivotedat 323 under tension of spring 324 and having an extension 325 in theplane of the driving pawl 304. Attached to rocking member 305 is anoperating arm 326 having an extension 321, which passes under the pawl304.

Cam member 3I2, when operated in successive steps, causes its cam apex3| 3 to operate a bell crank cam follower 330 pivoted at 33I and havingan operating contact pair I 54 in Figs. '1 and 11, appearing in circuitsas I54 in I3, Fig. 1, and 251 in I4, Fig. 1.

Break signal annunciators, which may be either of visible nature oraudible, or both, are provided at 333 and 334 in substations I5 and I6,respectively, Fig. 1, under control of slow-torelease relays I58 and260, respectively.

Break signal annunciators are provided also at 336, 331, 338, and 339 inthe central omces, Fig. 1. machine are operated by lever I33 No. 6 andcontrol an annunciator 336 or 338, Fig. 1. (3ontacts 34I, Figs. '7 and11, in, any B extensor machine are operated by follower 330 and cam apex3I3.

Break signal operation Function of the break signal system is to operatea signal device 334 at substation I6, Fig. 1, in response to operationof break key I56 at substation I5. With cam member'3l2, Fig. 7, asshown, with relay 260, Fig. 1, adjusted for a delay of .2 second andwith transmission at 390 operations per minute, the key I56 must be heldopen for one second to operate the signal device 334 and must be heldopen thereafter as long as continuous operation of the signal device isdesired.

When key I56 is maintained open, magnet 45, Fig. 1, is ole-energized andremains in de-energized condition, starting the cam sleeve 31, Figs. 2.3, and 10, and maintaining it in continuous rotation, and in each suchrotation adjusting all swords 86 and H3 to spacing position and settingall contact springs.l33, Nos. 1 to 6, inclusive, to spacing position. Ateach rotation of multiplex distributor brush I61, transmission of apermutation code signal, namely: marking, marking, spacing, marking,marking, is effected from marking battery I12 to resistor I13, contactI15, contact spring I33 No. 6, now in spacing position, local conductorI18, contacts I33 Nos. 1, 2, 4, and 5, and cable I8 ,to multiplexsegments I, 2, 4, and 5, and from spacing battery I16 through resistorI11, contact and spring I33 No. 3, and cable I8 to multiplex segment No.3.'

Receipt of the described transmitted permutation code signal in the Bextensor I4 results in tripping the triggers 233, Nos. 1, 2, 4, and 5,Fig. 7, and starting the cam sleeve 204. Cam 222 and cam follower 231permit springs 243 and operating arms 236 to operate latches 2I5, Nos.1, 2, 4, and 5, clearing all lugs 308 from the path of bail blade 301,and while follower arm 239 remains within the notch of cam 222, the cam300 permits its follower 30I to rotate, causing the driving Contacts340, Fig. 13, in any A extensorv pawl 304 to rotate the cam member 3I2one step, where it is held by detent 322, after which cam follower 30lis retired by cam 300. Repeated reception of the described "figuresshift code signal" advances the cam member 3I2 in repeated steps untilpawl 304 engages the last ratchet tooth 3I5, and apex 3I3 operates itsfollower 330 toopen the contacts 251 in I4, Fig. 1. Repeatedtransmission of figures shift code signal must continue further until,after .2 second, the relay 280 releases its armature, and the signaldevice 334 becomes energized and will continue energized as long as keyI56 is maintained open.

Upon reclosure of key I56, a continuous marking signal is transmittedover extension line conductor I1, the signal in the multiplex channelresponsively changes to marking nature for the remainder of the instantcycle of the A extensor. B extensor I4 therefore registers a code signalwhich may be for T, M, N, V or "letters shift,"

depending upon the number of impulse intervals of the instant cycle ofthe A extensor following the change from spacing to marking condition ofthe transmitter,-and upon operation of cam follower 30I, the bail blade301 engages at least one lug 308 as a fulcrum, upon which fulcrum therocking member 305 is rocked by power received through movable pivot 303from spring 302. R0- tation of member 305 lifts arm 326 and lug 321 andthereby lifts pawl 304 which in turn engages and lifts detent 322,releasing the cam member 3I2 which is returned by spring 3I6, releasingits cam follower 330 and reclosing contact pair 251 in I4, Fig. 1, thusreenergizing relay 260 and terminating energization of signal device.334.

Transmission of the break signal has been effected by a prolongedinterval of spacing signal in the extension line conductors, duringwhich a permutation code signal has been repeated several times in themultiplex channel. The prolonged spacing signal is not one of thethirty-two usable signal combinations of a start-stop permutation,diifering as it does from the blank combination by including no rest orstop pulse. It is not one of the thirty-one usable combinations of amultiplex code, but corresponds to the idle condition of a multiplexchannel, which is not a signaling condition. Thus, the break signalwhich traverses the extension lines belongs neither to the start-stopnor the multiplex code, and is therefore an ultra-code signal whichproduces, through, the use of suitable translating devices, a repetitionof a predetermined codesignal of the communication code of signals inthe multiplex channel.

A break signal originating on extension circuit I1 either by key I 56 orby an accidental break in theline I1 will operatecentral oflice signaldevices 336 and 331, while a break signal originating on extensioncircuit 28 either by key 258 or by an accidental break in the line 28will operate central oflice signaldevices 338 and 339. In each central"office, signal device 336 or 338 identifies tacts I54 by ratchet cam 3I2have been accomplished. The receiving printer at station I6 representedby selector magnet 26L will thus be placed out of correspondence withthe home recorder at station I 5, represented by selector magnet I59, ifthe printers had been operating previously in the letters shift"condition. Compensation for this condition may be had in an operatingroutine according'to which the operator at the message transmittingstation, such as station l5, before sending any character printingsignals, sends a signal for placing both printers in the desired lettersshift or "figures shift condition.

The placing of one recorder out of correspondence with the other, uponoperation of the break signal key, may b obviated by providing that thecode signal combination to be transmitted in the multiplex channel shallcorrespond to,the instant case shift condition of the recorders, andtherefore to the last transmitted case shift signal, instead of being apredetermined, invariable signal combination. A system for automaticallygenerating either of two case shift signals according to which of thosesignals had been most recently transmitted, the system being readilyadaptable to the apparatus of the present invention, is disclosed incopending application Serial No. 167,163: filed October 4, 1937, by L.M. Potts.

Specificextensor machines and specific circuits have been described inthis specification to illustrate the invention, but other mechanicaldevices may embody the invention equally well and efiect the desiredresults in satisfactory manner within the scope of the invention. 7

What is claimed is:

1. A method of transmitting a break signal in multiplex extensioncircuit operation which comprises transmitting a break signal in theform of a prolonged ultra-code signal, translating the ultra-code signalinto a predetermined code signal of the code of communication codesignals, and transmitting the selected code signal repeatedly.

2. A method of transmitting a break signal in a multiplex extensioncircuit system which comprises transmitting a break signal in the formof a repeated predetermined code signal of the code of communicationsignals, translating the repeated code signal into a prolonged signal ofultra-code nature, and transmitting the prolonged signal in an extensioncircuit of the system.

3. In a multiplex extension circuit system, a plurality of stations, amultiplex channel connecting two of said stations, an extension lineconnecting one of said two stations to a further one of said stations,means for transmitting a prolonged break signal over said extensionline, and means responsive to receipt of said prolonged break signal fortransmitting recurrently over said multiplex channel a predeterminedcode signal selected from the multiplex channel communication code ofsignals.

4. In a multiplex extension circuit system, a plurality of stations, amultiplex channel connecting two of said stations, an extension lineconnecting one of said two stations to a further one of said stations,means for transmitting recurrently over said multiplex channel apredetermined code signal selected from the multiplex channelcommunication code of signals, and

- means responsive to said recurrently transmitting means fortransmitting a prolonged break signal over said extension line.

5. In a multiplex extension circuit system, a

plurality of stations, a multiplex channel connecting two of saidstations, an extension line connecting one of said two stations to afurther one of said plurality of stations, means for transmitting oversaid extension line permutation signal impulses of a predeterminedcommunication code signal accompanied by an ultra-code signal impulse ofpredetermined nature, further means for transmitting over said extensionline repeatedly and continuously the permutation signal impulses of saidpredetermined code signal accompanied by a further ultra-code signalimpulse of other than said predetermined nature, and translation meansresponsive to said further ultra-code signal impulse to transmitrepeatedly into said multiplex channel a different predetermined codesignal.

6. In a multiplex extension circuit system, a plurality of stations, amultiplex channel connecting two of said stations, an extension lineconnecting one of said two stations to a further one of said pluralityof stations, means for transmitting repeatedly over said multiplexchannel a code signal constituting one of a code of communication codesignals, counting means responsive to said code signal when repeated,and means controlled by said counting means and effective to transmit anultra-code signal over said extension line.

7. In a multiplex extension circuit system, a plurality of stations, amultiplex channel connecting two of said stations, an extension lineconnecting one of said two stations to a further one of said pluralityof stations, means for transmitting repeatedly over said multiplexchannel a code signal constituting one of a code of communication codesignals, rotary counting means responsive to said code signal whenrepeated, means controlled by said counting means and effective after apredetermined number of counts to transmit an ultra-code signal oversaid extension line, and adjustment means rotatable coaxially with saidrotary counting means for altering the said number of counts.

8. In a multiplex extension circuit telegraph system, a multiplexchannel, a counting member, electrical contacts controlled by saidcounting member when in a predetermined position reached throughsuccessive counting operations, means responsive to a predetermined codesignal received over said multiplex channel and controlling saidcounting member to effect successive counting operations, a simplexextension line including said electrical contacts, and mechanism in saidextension line responsive to control only by said electrical contacts.

9. In a start-stop receiving device, a plurality of permutation members,a first cam sleeve, means for starting said first cam sleeve intooperation in response to a received signal, means operable selectivelyby said first cam sleeve to set predetermined ones of said membersaccording to received signals, a second cam sleeve,

' cording to received signals, a second cam sleeve,

means controlled by said first cam sleeve to start a,avo,sso

said second cam sleeve, and means operable by said second cam sleeve inresponse to a received signal to change the electrical condition of someof said electrical retransmission members.

11. In a multiplex extension circuit telegraph system, a centralstation, a multiplex transmission system terminating in said centralstation,

a normally closed extension circuit terminating in said central station,first repeating means connected to said multiplex system and to saidextension circuit responsive to a prolonged open condition of saidextension circuit and eflective to transmit a repeated predeterminedcode signal into said multiplex transmission system, second repeatingmeans connected to said multiplex system and to said extension circuitresponsive to a repeated predetermined code signal received from saidmultiplex transmission system and effective to transmit a prolonged opencondition into said extension circuit, a first annunciator deviceconnected to said first repeating means, operative when said firstrepeating means is responding to the prolonged open condition of thefirst-mentionedextension circuit, and a second annunciator deviceconnected to said second repeating means, operative when said secondrepeating means is transmitting into the second-mentioned extensioncircuit a prolonged open condition.

12. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel,

, storage means for receiving and storing a code signal from saidmultiplex channel, retransmitting means for retransmitting said storedcode signal into said extension line under control of said storagemeans, starting means controlled periodically by said multiplex channelto start said retransmitting means, and wholly mechanical blocking meansfor preventing operation of said starting means and controlled by saidstorage means to unblock said starting means when a signal is stored insaid storage means.

13. In a multiplex extension circuit system. a simplex extension line. amultiplex retransmitting channel, a multiplex receiving channel, aretransmission mechanism having a winding in said extension line toretransmit signals into said retransmitting multiplex channel. areceiving mechanism having windings in said receiving multiplex channeland having contacts responsive to signals in said multiplex receivingchannel to retransmit signals into said extension line. echo contacts insaid receiving mechanism, means for operating said echo contacts and forholding said echo contacts in operated condition whilev said receivingmechanism is transmitting, and

a circuit including said echo contacts and a winding in saidretransmission mechanism and effective to render said retransmissionmechanism unresponsive to signals in said extension line.

14. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel.

means to receive from ,said start-stop channel transmitting means andeil'ective to unblock said retransmitting means responsively to receiptof eachreceived code signal.

16. In a multiplex extension circuit system, a

start-stop extension line, a multiplex channel,

first storagemeans, receiving means for receiving a code signal fromsaid multiplex channel a and for storing the'" received signalin saidfirst storage means, second storage means, transfer' means fortransferring said stored code signal into said second storage means,retransmittlng means for retransmitting said stored code signal intosaid extension line under control of said second storage means, andblocking means controlled by said receiving means for blocking saidretransmitting means and eflective to unblock said retransmitting meansresponsively to receipt of each received code signal.

17. In a telegraph repeater, .a start-stop re- 1 eeiver, a multiplexretransmitter, a constantly rotating shaft, a first cam member, firstmeans responsive to a received signal to couple said first cam member tosaid shaft, a second cam member, second means controlled by said firstcam member to couple said second cam member to said shaft, a third cammember, third means controlled by said retransmitter to couple saidthird cam member to said shaft, and further means controlled by saidsecond cam member while in stop position to prevent operation of saidthird means.

18. In a telegraph repeater, a rotary member,

means'responsive to a received signal to start said rotary member, aretransmission control device, electromagnetic means to start saidretransmission controldevice at regular periodic intervals, and meanscarried by said rotary member to render ineffective said electromagneticmeans.

19. Ina telegraph repeating system, means to register severally theimpulses of a received code signal oi a plurality of impulses, and meansto retransmit for each registered code signal a corresponding codesignal of a smaller plurality of impulses which impulses for somereceived code signals correspond to a series of impulses embodied in thereceived and registered code signal but which impulses for onepredetermined received code signal vary from the series of impulsescomprising the received and registered code signal.

20. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel,

storage means for receiving and storing a code start-stop extensionline, a multiplex channel,-

storage means for receiving and storing a code signal from saidmultiplex channel, retransmitting means for retransmitting said storedcode signal into said extension line under control of saidstorage-means, electromechanical starting means fpr said retransmittlngmeans energizable periodically under control of said multiplex channelirrespective of the presence or absence of signals in said storagemeans, and wholly mechanical means for blocking the mechanical portionof said starting-means and controlled by saidstorage-means to unblockthe mechanical portion of said starting means when a signal is stored insaid storage means.

22. In a multiplex extension circuit system, a

start-stop extension line, a multiplex channel,

electromagnetic means for registering a code signal received from saidmultiplex channel, mechanical storage means controlled by saidregistering means for storing a code signal registered thereby,retransmittlng means for retransmitting said stored code signal intosaid extension line under control of said storage means, electromechanical starting means for said retransmitting means energizableperiodically under control of said multiplex channel irrespective or thepresence or absence of signals in said storage means, and whollymechanical means for blocking the mechanical portion of said startingmeans and controlled by said storage means to unblock the mechanicalportion of said starting means when a signal is stored in said storagemeans.

23. In a multiplex extension circuit system, a multiplex system, astart-stop extension line, means to receive from said multiplex systemand to store mechanically a code signal, retransmitting means toretransmit said stored signal to said start-stop extension line, andmeans associated with said retransmitting means and independent of anyelectrical signaling impulses in said multiplex system to reset saidstoring means to efiect deleting of a retransmitted code signal fromsaid storing means.

24. In a multiplex extension circuit system, a multiplex system, astart-stop extension line, means to receive from said multiplex systemand to store mechanically a code signal, retransmitting means toretransmit said stored signal to said start-stop extension line, andmeans wholly controlled by said retransmitting means to reset saidmechanical storing means.

25. In a multiplex extension circuit system, a multiplex system, astart-stop extension line, means to receive from said multiplex systemand to-store mechanically a code signal, retransmitting means toretransmit said stored signal to said start-stop extension line, andmeans wholly controlled mechanically by said retransmitting mitting theprolonged signal in an extension circult of the system.

27. A method of transmitting a break signal in multiplex extensioncircuit operation which comprises transmitting in an extension circuit abreak signal in the form of a prolonged ultracode signal, translatingthe ultra-code signal into a predetermined code signal of the code ofcommunication code signals, transmitting the lected code signalrepeatedly in a multiplex channel, translating the repeated code signalinto a prolonged signal of ultra-code nature, and transmitting theresulting prolonged signal in another 61" extension circuit.

28. A method of transmitting a break signal in multiplex extensioncircuit operation which comprises transmitting in an extension circuit abreak signal in the form of a prolonged ultra-v 10; code signal,translating the ultra-code signal into a predetermined code signal ofthe code of communication code signals, transmitting the selected codesignal repeatedly, translating the code signals in excess of apredetermined num- 152 her into a prolonged signal of ultra-code nature,and transmitting the resulting prolonged signal in another extensioncircuit.

29. In a multiplex extension circuit system, amultiplex channel, anextension circuit, and a re-' transmitting device interconnecting saidchannel and said extension circuit, said retransmitting device includingsignal responsive means controlled by signals received from saidmultiplex channel, signal transmitting means for im- 25. pressingsignals upon said extension circuit, me-

chanical storage means interposed between said signal responsive meansand said signal transmitting means having a storing position in whichsignals from the multiplex channel are stored in said storage means anda transferring position in which stored signals are transferred to saidtransmitting means, and means to retain said storage means in anintermediate position until said transmitting means is ready to receivea transferred signal.

30. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel, first storage means, receiving means forreceiving the code signal from said extension line and for storing thereceived signal in said first storage means, second storage means,transfer means for transferring said stored code signal into said secondstorage means, retransmitting means for retransmitting said stored codesignal into said 4%. multiplex channel under control of said secondstorage means, and means controlled jointly. by said receiving means andsaid multiplex channel for setting in operation said retransmittingmeans. i 50 31. In amultiplex extension circuit system, a start-stopextension line, a multiplex channel, first storage means, receivingmeans for receiving the code signal from said extension line and forstoring the received signal in said first storage means, second storagemeans, transfer means for transferring said stored code signal into saidsecond storage means, retransmittin'g means for retransmitting saidstored code signal into said multiplex channel under control of saidsecond storagemeans, and means controlled primarily by said receivingmeans and secondarily by said multiplex channel for setting in operationsaid retransmitting means.

32. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel, first storage means, receiving means forreceiving the code signal from said extension line and for storing thereceived signal in said first storage means, second storage means,transfer means for transferring said stored code signal into said secondstorage means, retransmitting means for retransmitting said stored codesignal into said multiplex channel under control of said second storagemeans, means controlled periodically by 75 "said multiplex channel andnormally ineflective 2,270,889 for starting said retransmitting means,and

electromagnetic means for registering a code signal received from saidmultiplex channel, first mechanical storage means controlled by saidsignal registering means, second mechanical storage means controlled bysaid first mechanical storage means, retransmitting means forretransmitting said stored code signal into said extension line undercontrol of said second storage means, and means controlled by saidretransmitting means for timing the setting of said second storage meansunder control of said first storage means.

34. In a multiplex extension circuit system, a start-stop extensionline, a multiplex channel, electromagnetic means for registering a codesignal received from said multiplex channel, first mechanical storagemeans controlled by said signal registering means, second mechanicalstorage means controlled by said first mechanical storage means,retransmitting, means for retransmitting said stored code signal intosaid extension line under control of said second storage means, meanscontrolled by said retransmitting means for timing the setting of saidsecond storage means under control of said first storage means, andmeans actuated by said retransmitting means for resetting said firststor- I age means.

35, In a multiplex extension circuit system, a. multiplex channel, anextension circuit, and

' a retransmitting device, interconnecting said channel and saidextension circuit, said retransmitting device including signalresponsive means individual to each impulse of a signal combinationcontrolled by signals received from said multiplex channel, signaltransmitting means for impressing signals upon said extension circuit,

, and mechanical storage means interposed be tween said signalresponsive means and said signal transmitting means having normal,storing and transmitting positions.

36. In a multiplex extension circuit system. a multiplex channel, anextension circuit, and a retransmitting device interconnecting saidchannel and said extension circuit, said retransmitting device includingsignal responsive means individual to each impulse of asignal'combination pressing signals upon said extension circuit, andcontrolled by signals received from said multiplex channel, signaltransmitting means for immechanicalv storage means interposed betweensaid signal responsive means and said signal transmitting means havingnormal, conditioned and actuated positions.

37. In a telegraph system, an incoming line, an outgoing line, and meansfor repeating signals from said incoming to said outgoing line includingastart-stop receiving distributor, a continuously operable transmittingdistributor, means controlled by said receiving distributor forinitially storing signals received from said incoming line, normallylocked means for intermediately storing signals received from saidinitial storing means, means controlled by said receiving distributorfor unlocking and relocking said intermediate storing means, means forimpressing signals upon said transmitting distributor, and meanscontrolled jointly by said receiving distributor and said transmittingdistributor for controlling said last-mentioned means according to thesignal storage condition of said intermediate storing means.

38. In a start-stop receiving device, a selector magnet, signalregistering means conditioned by said magnet in accordance with receivedsignals, a first cam sleeve to position said signal registering meansinto operative relation with respect to said magnet, means controlled bysaid magnet to place said first cam sleeve into operation in response toa received signal; a second cam sleeve, means controlled by said firstcam

